MechanicalRebuild shelfHand tools, works as-is

Screws and standoffs

Also called M3, laptop screw, brass standoff, Torx.

Laptop screws are tiny and specific (often M2 and M2.5). PC standoffs and optical-drive screws are M3. Printers mix plastic bosses with self-tappers. A mixed jar is how you strip a laptop boss. Bag them by donor.

If you are new to this category

Rods, gears, belts, magnets, screws, and boxes. Printers are the best source of straight steel rod and toothed belts. Screws from a laptop are tiny and specific; a random screw in a laptop hole strips the plastic. Bag them by the machine they came from.

If two parts were meshing or riding together, keep them as a pair. A gear from one toy rarely fits a gear from another.

Inside a hard drive

The two curved blocks on the steel plates are the magnets, and they are the prize. Slide them apart. Do not pry straight up. The flat coil on the arm is a short-travel motor. The platters are not a useful material, and on some drives they are glass.

Specification. The right-hand column is what is typical. The label on the part in your hand wins if they disagree.
What to look for	Usual figure
Drive	Phillips, Torx T5–T10 on laptops and hard drives, occasional security Torx
Thread	M2, M2.5, M3 are the electronics set. Self-tappers are not machine screws.

Volts are electrical pressure, amps are how much current is flowing, and ohms are how hard the part resists that flow. A higher voltage than the part was built for is how salvage parts die on the bench. If a cell in the table says “read the stamp”, that stamp is the whole specification.

What people actually use it for

The next teardown
Mounting a board
Standoffs that set a board height

Leave this one when

The head is already rounded. Recycle it; it will only round again.

Buying a new one is the better idea when

A small machine-screw kit. Use salvage screws for the machine they came from.

How to tell if this one still works

A driver that fits. If it cammed out once, the head is already done.

Tools you will want: The correct driver.

Where people actually find it

5 notes, most useful first. “Leave it” means the part is in that machine and you should not take it: it is dangerous, worn out, or only useful if you already know that exact repair.

Harvest at a glance
From	Call	How many	How often	Where it sits
Desktop PC	Worth it	a bag	always	Throughout.
Laptop	Worth it	a labeled bag	always	Everywhere.
Hard disk drive	Bonus	several	always	Lid and magnet keepers.
CD / DVD / Blu-ray drive	Bonus	several	always	Case.
Keyboard	Bonus	several	usually	Case.

Worth pullingDesktop PCa bag · always
In this particular machine
M3 screws, standoffs, drive screws. 6-32 on some older cases.
Where to look
Throughout.
How to get it out
Bag and label. Do not mix with laptop screws.
The condition to expect
Good.
Worth pullingLaptopa labeled bag · always
In this particular machine
M2 and M2.5, several lengths. The length matters.
Where to look
Everywhere.
How to get it out
One bag per model.
The condition to expect
Good if the heads are not stripped.
Bonus, if you are already in thereHard disk driveseveral · always
In this particular machine
Torx, some with retained washers.
Where to look
Lid and magnet keepers.
How to get it out
Bag them.
The condition to expect
Good.
Bonus, if you are already in thereCD / DVD / Blu-ray driveseveral · always
In this particular machine
Small Phillips, some M2.
Where to look
Case.
How to get it out
Bag them.
The condition to expect
Good.
Bonus, if you are already in thereKeyboardseveral · usually
In this particular machine
Small Phillips, sometimes the only thing worth bagging.
Where to look
Case.
How to get it out
Bag them.
The condition to expect
Good.